Contents
ssptrs - solve a system of linear equations A*X = B with a
real symmetric matrix A stored in packed format using the
factorization A = U*D*U**T or A = L*D*L**T computed by
SSPTRF
SUBROUTINE SSPTRS(UPLO, N, NRHS, AP, IPIVOT, B, LDB, INFO)
CHARACTER * 1 UPLO
INTEGER N, NRHS, LDB, INFO
INTEGER IPIVOT(*)
REAL AP(*), B(LDB,*)
SUBROUTINE SSPTRS_64(UPLO, N, NRHS, AP, IPIVOT, B, LDB, INFO)
CHARACTER * 1 UPLO
INTEGER*8 N, NRHS, LDB, INFO
INTEGER*8 IPIVOT(*)
REAL AP(*), B(LDB,*)
F95 INTERFACE
SUBROUTINE SPTRS(UPLO, [N], [NRHS], AP, IPIVOT, B, [LDB], [INFO])
CHARACTER(LEN=1) :: UPLO
INTEGER :: N, NRHS, LDB, INFO
INTEGER, DIMENSION(:) :: IPIVOT
REAL, DIMENSION(:) :: AP
REAL, DIMENSION(:,:) :: B
SUBROUTINE SPTRS_64(UPLO, [N], [NRHS], AP, IPIVOT, B, [LDB], [INFO])
CHARACTER(LEN=1) :: UPLO
INTEGER(8) :: N, NRHS, LDB, INFO
INTEGER(8), DIMENSION(:) :: IPIVOT
REAL, DIMENSION(:) :: AP
REAL, DIMENSION(:,:) :: B
C INTERFACE
#include <sunperf.h>
void ssptrs(char uplo, int n, int nrhs, float *ap, int
*ipivot, float *b, int ldb, int *info);
void ssptrs_64(char uplo, long n, long nrhs, float *ap, long
*ipivot, float *b, long ldb, long *info);
ssptrs solves a system of linear equations A*X = B with a
real symmetric matrix A stored in packed format using the
factorization A = U*D*U**T or A = L*D*L**T computed by
SSPTRF.
UPLO (input)
Specifies whether the details of the factorization
are stored as an upper or lower triangular matrix.
= 'U': Upper triangular, form is A = U*D*U**T;
= 'L': Lower triangular, form is A = L*D*L**T.
N (input) The order of the matrix A. N >= 0.
NRHS (input)
The number of right hand sides, i.e., the number
of columns of the matrix B. NRHS >= 0.
AP (input)
Real array, dimension (N*(N+1)/2) The block diago-
nal matrix D and the multipliers used to obtain
the factor U or L as computed by SSPTRF, stored as
a packed triangular matrix.
IPIVOT (input)
Integer array, dimension (N) Details of the inter-
changes and the block structure of D as determined
by SSPTRF.
B (input/output)
Real array, dimension (LDB, NRHS) On entry, the
right hand side matrix B. On exit, the solution
matrix X.
LDB (input)
The leading dimension of the array B. LDB >=
max(1,N).
INFO (output)
= 0: successful exit
< 0: if INFO = -i, the i-th argument had an ille-
gal value